Following up the previous two posts (here and here) re docx:
First, David Boundy says that tomorrow there will be a Federal Register Notice in which the PTO delays by three months the imposition of the $400 charge for failure to file in "docx".
Second, Carl Oppedahl has written a superb explanation of the problems with docx, and how the PTO has repeatedly lied about this being a standard:
If you're a practitioner, please sign the letter to Director Vidal, urging her to read his explanation.
I will be shocked if the PTO persists in this docx nonsense.